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101.
Everyday memory following traumatic brain injury 总被引:1,自引:0,他引:1
G. Kinsella D. Murtagh A. Landry K. Homfray M. Hammond L. O'Beirne L. Dwyer M. Lamont J. Ponsford 《Brain injury : [BI]》1996,10(7):499-508
Residual memory deficits may represent a problem to the everyday functioning of a large number of people, including those who have sustained traumatic brain injury (TBI). The present exploratory study sought to investigate the interrelationships between subjective memory reports, performance on traditional memory tests, and performance on tests of prospective memory. These interrelationships were contrasted between a group of 24 adults who had sustained TBI and a group of 24 matched control subjects. Prospective memory was hypothesized to be indicative of everyday memory functioning. The results provided preliminary evidence that prospective memory tests are sensitive to TBIrelated neurological impairment and, in comparison to traditional tests, may be better indicators of functional memory capacity. This pattern was particularly true for control subjects, possibly because TBI subjects had difficulties in evaluating their memory functioning. 相似文献
102.
103.
Yannick Poquet Patricia Constant Franck Halary Marie-Alix Peyrat Martine Gilleron François Davodeau Marc Bonneville Jean-Jacques Fournié 《European journal of immunology》1996,26(10):2344-2349
The stimulation of human γδ T cells by mycobacteria occurs through recognition of four distinct nonpeptide phosphorylated antigens termed TUBag1–4. Among these latter, TUBag4 has already been biochemically characterized as a γ-X derivative of 5′-deoxythymidine triphosphate (Constant, P., Davodeau, F., Peyrat, M. A., Poquet, Y., Puzo, G., Bonneville, M. and Fournié, J.-J., Science 1994. 264: 267). However, despite chemical synthesis of weakly stimulatory nucleotide-containing analogs, these mycobacterial compounds remained the sole nucleotide-containing antigens actually isolated from natural sources. Here, we present the complete isolation of the TUBag3 antigen from Mycobacterium fortuitum and demonstrate that this nonpeptide molecule contains a 5′-UTP nucleotide moiety. On selected Vγ9/Vδ2 clones, T cell responses can be triggered with nanomolar concentrations of TUBag3. Like crude mycobacterial extracts, this purified nucleotide conjugate elicits a strong polyclonal response of γδ PBL from healthy donors. Furthermore, we present evidence that this compound is distinct from the recently synthesized γ-isopentenyl 5′-UTP, a nucleotide conjugate of isopentenyl pyrophosphate that was found to be stimulatory for human γδ T cells (Tanaka, Y., Morita, C. T., Tanaka, Y., Nieves, E., Brenner, M. B. and Bloom, B. R., Nature 1995. 375: 155). Since it appears that both mycobacterial nucleotide antigens are molecules structurally related to peculiar precursors of nucleic acid synthesis, we propose that TUBag-reactive T cells might be specifically devoted to surveillance of proliferating cells. 相似文献
104.
Interaction of native proteinaceous antigens during the recognition and the effector phases of an immune response leads to antigenic conformational modifications which may elicit additional specific immune response. Protein cross-linking and conformation restraining formaldehyde and glutaraldehyde have been extensively used in vaccine preparation, but the relative efficiencies of conformational restraint at concentrations similar to those used in vaccine preparation have not been investigated. We addressed this issue by comparing the extent of conformational restraint of virus proteins in formaldehyde- and glutaraldehyde-treated virus preparations by monitoring the fluorescence intensities (I320) of infectious bursal disease virus preparations (IBDV) and those of untreated virus during thermal denaturation. Formaldehyde was found to cause no detectable conformational restraint at 0.01% and only very weak restraint at 1%, while glutaraldehyde caused very strong conformational restraint at 0.01%. It is proposed how conformational restraint of proteinaceous antigens may alter ensuing immunity. 相似文献
105.
Selective gap-junctional communication capacity of transformed and non-transformed rat liver epithelial cell lines 总被引:5,自引:2,他引:3
To investigate whether a selective intercellular communicationexists between transformed epithelial cells and their counterparts,the homologous and heterologous communication capacities offour rat liver epithelial cell lines were compared with theirexpression of transformed phenotypes. All four cell lines showedreasonably good homologous junctional communication capacity,as measured by the dye-transfer assay. In heterologous co-cultures,the non-transformed cell line IAR 20 did not communicate withthe transformed cell lines IAR 61 or IAR 27 F. Thesetwo cell lines showed a high degree of transformed phenotypessuch as cell morphology, growth in soft agar and expressionof -glutamyltrans-peptidase activity. Another cell line IAR27 E, showed the least degree of transformation and it communicatedwith IAR 20 cells. Thus, it appears that there is an inversecorrelation between the extent of expression of transformedphenotypes by rat liver epithelial cells and their ability tocommunicate with non-transformed counterparts. There was noheterologous intercellular communication between any combinationof IAR 27 E, IAR 27 F and IAR 61 cell lines. 相似文献
106.
107.
Charles B. Pratt Edwin C. Douglass William H. Meyer F. Ann Hayes Marc E. Horowitz Elizabeth I. Thompson Loraine Avery 《Investigational new drugs》1989,7(2-3):209-211
Summary 4 -Deoxydoxorubicin was given to 15 patients with drug-resistant pediatric malignant solid tumors with the objectives of determining the maximum tolerated dosage and dose-limiting toxicity. Maximum tolerated dosage was 36 mg/m2 given IV once every 3 weeks. Dose limiting toxicity was myelosuppression, which was severe and prolonged. Therapeutic benefits were not observed for these patients. 相似文献
108.
Assessment of virulence of pigeon isolates of Salmonella enterica subsp. enterica serovar typhimurium variant copenhagen for humans 下载免费PDF全文
Pasmans F Van Immerseel F Hermans K Heyndrickx M Collard JM Ducatelle R Haesebrouck F 《Journal of clinical microbiology》2004,42(5):2000-2002
Salmonella enterica serovar Typhimurium variant Copenhagen was isolated from 5 of 152 (3.3%) feral pigeons from the city of Ghent (Belgium) and from 26 pooled fecal samples from 114 pigeon lofts (22.8%). These isolates belonged to phage type (PT) 99. Seven of the pigeon isolates were further compared in vitro to five human variant Copenhagen isolates, 2 isolates of PT 208, 1 isolate each of PT 120 and U302, and a nontypeable isolate. No differences in invasiveness in human intestinal epithelial Caco-2 cells were found. The human strains, however, were able to multiply significantly more inside human THP-1 macrophages than the pigeon strains. After inoculation of mice with a pigeon PT 99 strain, high numbers of Salmonella bacteria were shed with the feces, the internal organs were heavily colonized, and the animals showed severe clinical symptoms resulting in death. In conclusion, the less-pronounced ability of the pigeon variant Copenhagen strains to multiply inside human macrophages than human strains as well as the lack of human PT 99 isolates during 2002, despite the relatively high frequency of this PT in the pigeon population, suggest these strains to be of low virulence to humans. However, the high virulence for mice of the tested strain implies that rodents may act as reservoirs. 相似文献
109.
Summary Shortly after subcutaneous or intraperitoneal injection of nontoxic quantities of trypan blue into laying Japanese quails, red fluorescent yolk granules appear in the peripheral ooplasm of their oocytes at the end of the lampbrush stage or subsequently. Later a red fluorescence can be observed in the apical cytoplasm of the granulosa cells. The results obtained by this method confirm our previous results (Callebaut 1974) obtained by autoradiography after 3H-leucine administration and furnish interesting additional data. The trypan blue-induced fluorescence method gives a good indication of the permeability of the oocytal cortex and its derivative the germinal disc. The avian yolk which is, or has been peripherally assembled (primordial, true white and yellow yolk) can be characteristically labelled by the administration of trypan blue. The injection of higher, still nontoxic quantities of trypan blue has a prolonged retarding effect and permits the marking of a broader part of the germinal disc or eventually of the blastoderm which develops from it. 相似文献
110.
Rodríguez-Niedenführ M Vázquez T Choi D Parkin I Sañudo JR 《Clinical anatomy (New York, N.Y.)》2003,16(3):197-203
Supernumerary humeral heads of the biceps brachii muscle were found in 27 (15.4%) of 175 cadavers. They were bilateral in five cadavers and unilateral in 22 (8 left, 14 right), giving a total of 32 examples in 350 arms (9.1%). Depending on their origin and location, the supernumerary heads were classified as superior, infero-medial, and infero-lateral humeral heads. Previous studies were reviewed using this classification. The infero-medial humeral head was observed in 31 of 350 (9%) arms and was therefore the most common variation. The superior humeral head was observed in five (1.5%). The infero-lateral humeral head was the least common variation, observed only in one (0.3%) of 350 arms. A biceps brachii with three heads was observed in 27 of 350 (7.7%) arms and with four heads in five (1.4%) arms. 相似文献